Gauging device



Jan. 8, 1946.

W. F. ALLER GAUGING DEVICE Filed March 6, 1943 2` Sheets-Sheet 1- 3' INVENTOR. 6h/M6( j ATTORNEY.

Jan. 8, 1946. w. F. ALLER 2,392,301

GAUGING DEVICE Filed March e, 1945 2 sheetsheet 2 lNvENTOR,

ATTORNEY.

Patented Jan. 8, 1946 GAUGING DEVICE Willisrv Fay Aller, Dayton, Ohio, assigner to The Sheffield Corporation, Dayton, Ohio, a corporation .of Ohio ApplicatiomMarch 6, 1943, Serial No. 478,208

3 Claims.

This invention .relates to gauging devices and more particularly to gauging devices for measuring or comparing the pitch or lead of a screw threaded part.

One object of the invention is the provision of a thread pitch testing instrument .having a pair of relatively movable thread engaging members, with a gauging device responsive to the movement of one of these members, the thread engaging members having portions of substantially v form elongated in a direction away from vthe surface on which the part to be gauged is applied so that threaded parts of different diameters can be accommodated.

Another object is the provision of a threadv pitch testing instrument having a base provided with a flat work receiving surface and having a ,pair of relatively movable thread engaging blocks one of which cooperates with a gauging means which is arranged on a detachable supporting block independent of the main base, the construction being such that the gauging means and its supporting block may be readily removed from the base and be replaced by another gaug- 'gauge showing the mounting of a dial indicator form of gauging means;

Fig. 5 is a top plan View of a 'portion of the gauge shown in Fig. 4; and

Fig. 6 is an end view of the upper portion .of the same gauge. Y

Referring more particularly to the drawings, in which like parts have been given the same refer- 'ence numerals in the several views, and ,more

particularly with reference to Figs. .1 to 3, Il! designates a support or base having a plate portion II which is preferably .made asa separate member mounted in fixed position by means of suitable securingscrews 12. The top of the plate ,f

portion II is preferably a flat .horizontal surface on which the vthreaded parts to be gauged, `such for example as a screw, may be placed and pressed against a pair of relatively movable threadengazing blocks I3 and I4. The relative horizontal;

movement of the blocks I3 and vI4 produces :a `change in the position of a movable part of `the gauging means I5 vwhich is shown in the construction illustrated in these figures as a movable switch adapted to control electric circuits to produce a visible indication, as will be presently described.

The thread engaging block I4 has a horizontally extending leg I5 which rests on the portion `II .of the base, the latter having a groove Il slidably receiving the tongue on the leg I6 and `gui-ding the leg for horizontal movement towards and from the movable block I3. The plate portion II is provided with a series of spaced threaded holes I9 selectively engageable with a threaded locking stud that extends down through a yslot; 2|

in leg I6. By tighting the screw 2|) in -a selected hole I9, the stationary thread vengaging block I4 is held in a desired spaced relation from the movable block.

The movable block I3 has a forwardly extending portion 23 fixed to or formed asa part of a rather long back piece 24. The latter is `lined to a pair of parallel spring blades 25 which, in turn, are fixed to a stationary upstanding member 2.6. Screws 21 hold the latter in `fixed position on the base in back of the plate portion Il. The spring blades 25 control the movement of the block I3 so as to yieldingly permit horizontal movement towards and away from the block I4 while preventing any substantial travel of the block I3 towards the right or left as viewed in Fig. 3. The back piece 24 is provided with .an upstanding arm 28 which is preferably provided with a hardened insert 29 having a iiat surface facing towards the left as viewed in'Fig. `2.

Arranged on the base I0 at one side of the plate portion I I is a supporting block 30 which carries the gauging means I5. Suitable screws 3l form a' detachable connection between the block 3B and the gauging means I5, and locating dowels and y screws,32 detachably secure the supporting block in position on the base IU so that the gauging means is in a deiinitely .located position. The gauging means has a movable gauging element 34 adapted for horizontal movement under the control of the arm 28, the horizontal movement of the gauging element 34 causing movement of the switch arm 35 which makes and. breaks a pair'of electrical circuits by opening and closing a pair of switches 36 and 3l. Adjustable stops 38 .controlled by .adjustment knobs v39 provide adjustments determining theamount of travel permitted the arm 35 Vbefore it opens or closes the switches, .the construction illustrated being simiswitch 31 will be opened. Y

spacing of the work Y ranged on asuitable bracket 42 detachably car-1 VVried'by the base. Y Y

AsV willbe now apparent, when a screw is placed on the work receiving surface of theY base and pressed against the thread engaging blocks I3 and I4, the latter will'be spread apart, or drawn closer together if the spacing of the thread y engaging portions does not correspond to a mul- Fig. 3 represent a comparatively 'small workpiece v45 and a considerably larger workpiece 46, both resting on the upper surface of the plate II and both ineffective engagement with the blocks I3 and I4. Obviously only one or the other of the two workpieces 45 and 146 may be applied to the 4work engaging blocks at the same time, but either tiple of the thread pitch of the screw. The'block l 1block'I3 that YWhena standard screw of known pitch is applied on the base and pressed against these blocks, thereY will be a very small lateral l Vmovement of block I3 towards the left as viewed in Fig. 1, causing a small movement of the gauging element 34. With the `screw standard still held against the-gauging blocks, the knobs are manipulated until neither one of the two switches 3B and 31 are opened, and thus neither one of the two lamps inthe lamp housing@ will be energized. Any substantial movement of the block I3 from this position, however, will cause one or the other of the switches to be opened and energize one or the other of the two lamps in the lamp'housing.

The standard screw'is then-removed, and the screws to be testedare applied one at a time to the-work supporting surface of the base and pressed against the two gauging elements. If

"the pitch distance of the screw is too great, Ythe rmovable block I3 will move farther to the left than it did when the standard-screwrwas applied to it and the switch 36 will be opened, givingan apparent indication to the operator. If the pitch ofthe screw is smaller than it should be, the

Instead of obtaining the initial setting of the stationary block I4 by usingastandard screw,A the blocks I3 and I4 are constructed so that.

blockY I4 `may be very conveniently positioned v byusing a johnny-block, orlolocks i134 applied between the parallel vertical surfaces 45 and 45 of'the'thread engaging blocks. lThese surfaces are recessed soV as to lie in the same verticalVV planesrrthat pass through the centers of the thread ,engaging portions and the size of the johnny-blocks will thus correspond to! the engaging portions of the blocks I3 and I4.

It should be noted that the edge of the work supporting plate lies closely adjacent the movable work engaging block I3 to permit the thread should also be noted that the location of theA jpiock la, 'andthe block malen, is in between the vertical' planes Vcontaining the spring 'blades which carry thernovable block forryielding movement. I, f

In accordance with the present invention, the

Vwork engaging blocks are'so :arranged as to accommodate threaded members ofwidely dierent diameters. vThe circles shownin dash lines in 3italie place on the eifective parts of the threads at'or near the pitch diameter. The angle between the sides of the V ofcourse corresponds tothe one mayl be applied withouty changing these blocks other than making adjustment for `changes in pitch of the screw threads. The effective work f contacting portions of each of the two blocks I3 this block, that is, the portion presented towards the work, preferably extends substantially transversely 'of thework supporting surface, from a point rather closely adjacent the work supporting surface, and the lower portions are rather pointed while the upper portions of the block are truncated, the amount of truncation in the point of the V increasing as the block extends upwardly from lthe plate I When a threadedv part of comparatively small diameter is applied to the blocks, they engage points on the blocks nearthe lower portions, Where the truncation is less, since these smaller diameter threads will ordinarily. have a linerY pitch and a. much shorterthread surface. Threads of larger diameter will engage the more truncated portions of the `V section.Y Thus the engagement between the sides of the threads and the wedge shaped portions of the blocks will angle between adjacent sides of the thread to be tested.' When the thread to be tested. is

Y pressed against the blocks I3 and I4, Ythe movable block I3 will move laterally to accommodate the thread until 'the diverging sides ofthe two threads `engaged lby vthe two blocks will be inY full contact with the converging sides ofthe Y placed by another supporting block anda dial type indicator 43. 'As shownin Figs. 4, 5, and 6, the kdial type indicator 48 isfprovided with Yan indicator needle 49 which is responsive to the movement of a gauging element 5D. The element 50 is operated by the arm 2B.A Theindicator type of gauging means is of different shape th'an the Y gauging means I5 and requires a different form of supporting block, which as shownat 5I, is'

provided with the same hole spacing for engagement with the screws 32 to secure it on the base IIJ; V'Ihe block 5I is of such size that the gauging element 50 is carried in the same position as the gauging element 34. Th'e upper surface ofthe While the formsof apparatus herein described constitute preferred embodiments of the invention, it is to be understoodlthat the invention is notv limited tof these precise forms 'and that changes may be 'made lth'erein4 without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A gauging instrument for testing thread pitch comprising a base having a work receiving surface, a stationary thread engaging block fixed with respect to said base, a movable thread engaging block, means supporting said movable block for movement towards and from the stationary block, and gauging means operated by said movable block, said blocks each having a thread engaging and interfitting portion of substantially V section and elongated in a direction away from said base surface to engage threaded parts of diiierent diameters when presented to said base, the adjacent portions of said blocks having parallel fiat surfaces spaced apart a distance equal to the spacing between the centers of the thread engaging portions of the blocks,

2. A gauging instrument for testing thread pitch comprising a base having a iiat work receiving surface which at one end thereof is spaced away from the adjacent parts of th'e base, a stationary thread engaging block adjustably fixed on said base, a movable thread engaging block arranged closely adjacent to said end of the work receiving surface, means supporting said movable block for movement towards and from the stationary block, spring means controlling the movement of said movable block, and gaugtruncated V section and elongated in a direction substantially perpendicular to said base surface to engage threaded parts of different diameters when presented to said base, the degree of truncation increasing in accordance with the distance from the Work receiving surface, the adjacent portions of said blocks h'aving parallel at surfaces spaced apart a distance equal to the space between the centers of the thread engaging portions of the blocks.

3. A gauging instrument for testing thread pitch comprising a base having a work receiving surface, a stationary thread engaging block fixed with respect to said base, a movable thread engaging blo-ck arranged closely adjacent one end of said work receiving surface, means supporting said movable block for movement towards and from the stationary block, and gauging means operated by said movable block, said blocks each having a thread fitting portion of truncated substantially V section elongated in a direction away from said work receiving surface with th'e degree of truncation increasing in accordance with the distance from the work receiving surface to engage and intert threaded parts of different diameters at the pitch diameters thereof when presented to said surface.

WILLIS FAY ALLER. 

